Water heater insulated base

ABSTRACT

An insulated base for reducing thermal losses through the bottom of a water heater includes an inner body of insulating foam. The insulating body is between 0.75 inch and 2.5 inches thick, and extends laterally commensurate with the bottom diameter of the water heater. The insulating body is surrounded by a molded plastic cover for protection from physical impact. The insulated base may include an upturned lip around its perimeter to prevent water from entering or leaving the insulated base. A drain hole in such upturned lip allows collected water to escape upon reaching the level of the drain hole. The insulating body is preferably made from polyurethane, polyethylene, or polystyrene. The molded plastic cover that encases the insulating body is preferably made from roto-molded polyethylene or polypropylene plastic resin.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to apparatus for insulating water heaters, and more particularly, to an apparatus for reducing the loss of heat from a hot water heater into the supporting floor below.

2. Description of the Relevant Art

There has been a significant emphasis on conserving energy in the past several decades. Apart from potential money savings, energy conservation also helps to reduce the rate at which we consume fossil fuels, which are in limited supply, and which increase pollution of the atmosphere.

Such energy conservation efforts have included devices for better insulating hot water heaters. Most residential homes typically include at least one hot water heater, and if thermal losses from hot water heaters can be further reduced, potential energy savings are large. One such effort which has been made in the past is to provide insulted jackets, or blankets, that fit around the sides and top of a hot water heater to reduce the transfer of heat from the hot water heater storage tank. One example of such product is the hot water heater blanket commercially available from under the “Frost King” brand under Model Number SP57/11C. These types of blankets help to prevent loss of heat through the side walls and top of a hot water heater, but do not slow thermal losses through the bottom of the hot water heater.

There are commercially available insulation pads designed for installation below the base of a hot water heater. For example, a two inch thick by 24 inch diameter electric water heater pad is sold under the brand name “Insulfoam” by Home Depot Product Authority, LLC, both online and in its retail stores. This water heater pad is described as helping to save money by keeping heat from escaping from underneath a water heater. This pad is described as being made of high-density expanded polystyrene material.

While high-density expanded polystyrene offers relatively high compressive strength, it is essentially a foamed material; hydrocarbon solvents and ultraviolet rays will compromise its structure. In addition, it tends to be brittle, and physical impact with such material will tend to make it crack and/or break. Often, hot water heaters are located in garages or basements, locations where a water heater insulation pad is likely to be impacted by tools, children at play and/or gnawing rodents. In addition, the above-described water heater pad is incapable of protecting the base of the hot water heater from water damage due to a minor flood upon the floor used to support the hot water heater; once the level of the flooded water surrounding the hot water heater exceeds the thickness of the hot water heater pad, the flooded water will contact the base of the hot water heater, potentially causing corrosion damage. Further, such insulating pads do not offer any ability to temporarily collect or retain water sourced by the water heater itself due to pressure valve-released condensation runoff, or from leaks in the hot water heater storage tank.

Apart from insulated pads, non-insulated water heater drip pans, made of metal or plastic, are also known in the art. For example, a 24-inch diameter water heater drain pan, made from injection-molded polypropylene plastic material, is commercially available from Home Depot Product Authority, LLC, both online and in its retail stores, under Model No. 15021. This drain pan is described as helping to prevent damage from pressure valve-released condensation runoff or from leaks. It includes a pre-cut side opening for receiving a drain fitting that can be coupled to a drain tube. While this product serves to temporarily collect and drain water from a hot water heater, it does not provide any meaningful insulation to reduce thermal losses from the hot water heater to the underlying support surface.

Accordingly, it is an object of the present invention to provide a device for insulating the bottom of a hot water heater tank against thermal losses.

It is another object of the present invention to provide such a device that exhibits good resistance to hydrocarbon solvents, ultraviolet rays, and physical impact.

Still another object of the present invention is to provide the ability to isolate the base of a hot water heater from minor flooding upon the supporting surface, as well as collecting small amounts of runoff and/or leaking water originating with the hot water heater itself.

A further object of the present invention is to provide such a device that can be manufactured relatively easily and inexpensively.

These and other objects of the invention will become more apparent to those skilled in the art as the description of the present invention proceeds.

SUMMARY OF THE INVENTION

Briefly described, and in accordance with a preferred embodiment thereof, the present invention relates to an insulated base for a water heater. The insulated base is adapted to be placed below the bottom end of the water heater to reduce thermal losses through the bottom of the water heater. The insulated base of the present invention includes an insulating body made of insulating foam, and preferably having a thickness ranging between 0.75 inch and 2.5 inches. The lateral dimensions of the insulating body are commensurate with the bottom diameter of the water heater. The insulating body is surrounded by a molded plastic cover to protect the insulating body from physical impact.

The molded plastic cover includes a lower surface for resting upon a supporting surface, e.g., the foundation of a home. The molded plastic cover also includes an opposing upper surface for receiving the bottom end of the water heater. In one embodiment, the insulated base is essentially flat, e.g., in the form of a disc. In an alternate embodiment, the insulated base includes an upturned lip extending about its outer perimeter, serving to prevent water from entering or leaving the insulated base; a drain hole may be formed in such upturned lip for allowing collected water to escape from the insulated base when such collected water reaches the level of the drain hole.

The insulating body is preferably made from polyurethane, polyethylene, or polystyrene. The insulating body may be formed in at least two different ways. In a first method, the insulating body is formed first, for example, in a mold; after the insulating body has been formed, the plastic cover is thereafter molded over the insulating body. In a second method, the plastic cover is formed first; the insulating body is thereafter formed by injecting, for example, by spraying, insulating foam material inside the molded plastic cover.

When produced in accordance with the first of the above-described methods, the insulating body is preferably formed from either closed-cell, high-density polyurethane foam or closed-cell, high-density polyethylene foam. When produced in accordance with the second of the above-described methods, the sprayable insulating foam is preferably closed-cell spray polyurethane foam, although open-cell spray polyurethane foam may also be used.

The molded plastic cover that encases the insulating body is preferably made from roto-molded plastic resin. Preferably, the roto-molded plastic resin is polyethylene or polypropylene.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first embodiment of the present invention shown supporting the bottom end of an electric hot water heater.

FIG. 2 is a perspective view of a second embodiment of the present invention shown supporting the bottom end of an electric hot water heater and including an upturned lip extending about the bottom end of a water heater.

FIG. 3 is a partial cross-sectional view of the insulated base shown in FIG. 1.

FIG. 4 is a partial cross-sectional view of the insulated base shown in FIG. 2 according to one embodiment.

FIG. 5 is a partial cross-sectional view of the insulated base shown in FIG. 2 according to an alternate embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A first preferred form of an insulated base for a water heater in accordance with the teachings of the present invention is designated generally in FIG. 1 by reference numeral 20. Insulated base 20 is shown in FIG. 1 placed below the bottom end 22 of hot water heater 24. Bottom end 22 of water heater 24 is generally circular and has a characteristic diameter. In the embodiment shown in FIG. 1, insulated base 20 is generally circular, and has a diameter comparable to, and preferably, slightly larger than the characteristic diameter of bottom end 22 of water heater 24. As shown in FIG. 1, water heater 24 includes a typical drain valve 26 which may be used to periodically drain water, and collected sediment, from the hot water storage tank of water heater 24. As further shown in FIG. 1, water heater 24 may include a pressure relief valve 28 for releasing steam and/or over-heated water if the pressure within water heater 24 exceeds a safe limit. Conventional cold water inlet and hot water outlet fittings 30 and 32 are provided on the top of water heater 24 for connection to plumbing lines in the home.

Turning now to FIG. 3, insulating pad 20 is shown in greater detail. Insulating pad 20 includes an upper surface 40 for receiving the bottom end of a water heater, and an opposing lower surface 42 for resting upon a supporting surface, which might be the home foundation, a garage floor, or a raised platform provided specifically for supporting a water heater. Insulating pad 20 includes an inner insulating body 44 made of an insulating foam; this insulating foam is preferably formed of polyurethane, polyethylene, or polystyrene. Insulating body 44 preferably has a thickness ranging between 0.75 inch and 2.5 inches. For a given type of insulating foam, greater thicknesses provide a larger barrier to loss of heat from bottom end 22 of water heater 24. Using a thickness of approximately two inches provides a reasonable “R” value against thermal losses, and also serves to elevate bottom end 22 of water heater 24 by two inches or more above the supporting surface. The increased elevation of the bottom end 22 of water heater 24 not only assists when draining sediment through drain valve 26, but also serves to keep bottom end 22 of water heater 24 from being compromised by minor floods of collected water on the underlying foundation or other supporting surface.

Once again, insulating pad 20 may be circular in shape, and have a lateral size, i.e., diameter, commensurate with the bottom diameter of water heater 24. Conventional water heaters vary in diameter depending upon their storage capacity; insulating pad 20 may be made with a diameter ranging from 18 inches to 36 inches, depending upon the capacity of the water heater with which it will be used, so that the lateral size of insulating pad 20 is commensurate with the bottom diameter of the water heater. It should be understood, however, that insulating pad 20 need not be circular; for example, insulating pad 20 could be hexagonal, or even square, in shape, if desired, and in that case, its lateral dimensions, i.e., its length and width, would preferably each be slightly larger than the diameter of bottom end 22 of water heater 24.

Still referring to FIG. 3, insulating body 44 is encased within a molded plastic cover 46 that generally surrounds insulating body 44. Molded plastic cover 46 is preferably made from a roto-molded plastic resin, including either polyethylene or polypropylene. Plastic cover 46 serves to protect insulating body 44 from exposure to water, hydrocarbon solvents, ultraviolet rays, and physical impact by tools, children, and/or rodents.

The structure shown in FIG. 3 may be formed by at least two-different methods, and the selection of the material used to form insulating body 44 is influenced by which formation method is being used. For example, a manufacturer may elect to form insulating body 44 first, and then mold plastic cover 46 over insulating body 44. In this case, insulating body 44 is preferably formed from a high-density, closed-cell insulating foam, including without limitation, closed-cell, high-density polyurethane foam and closed-cell, high-density polyethylene foam. These high-density, closed-cell foams provide a higher compressive strength that more easily supports the significant weight of a typical hot water heater; conventional water heaters may weigh as much as 550 pounds when filled with water. The completed insulating body 44 is then inserted into a roto-molding machine, and plastic cover 46 is molded over insulating body 44, preferably using polyethylene resin or polypropylene resin.

Alternatively, the structure shown in FIG. 3 may be formed by first molding plastic cover 46 using a conventional roto-molding process. After plastic cover 46 is molded, spray foam insulating material 44 is injected into the hollow cavity of plastic cover 46. For example, closed-cell polyurethane insulating foam may be sprayed inside plastic cover 46. Such closed-cell polyurethane foam, after being injected, expands to about 35 to 50 times its original volume to entirely fill the hollow cavity of plastic cover 46, forming a rigid plastic insulating body having a compressive strength between 15 and 25 psi. If desired, open-cell polyurethane foam may be used instead, although it generally provides a lower “R” value for preventing thermal losses, and does not provide any significant compressive strength; thus, insulating pad 20 could become crushed somewhat if open-cell foam is used.

A second embodiment of the invention will now be described in conjunction with FIGS. 2, 4 and 5. As shown in FIG. 2, hot water heater 124 has its bottom end resting upon insulating pad 120. As in the first embodiment, water heater 124 includes a drain valve 126, a high-pressure relief valve 128, cold water inlet 130 and hot water outlet 132. Insulating pad 120 includes an outer perimeter having an upturned lip 160, and a drain hole 180 is provided in upturned lip 160 for draining water collected upon the upper surface of insulating pad 120.

Insulating pad 120 is shown in partial cross-section in FIG. 4. Insulating pad 120 includes an upper surface 140 for receiving the bottom end 122 of water heater 124, and an opposing lower surface 142 for resting upon a supporting surface. Insulating pad 120 includes an inner insulating body 144 made of an insulating foam, preferably of polyurethane, polyethylene, or polystyrene. In the embodiment illustrated in FIG. 4, insulating body 144 has a first height, or thickness, in the central portion thereof, and a second larger height along the outer perimeter thereof. The second, larger height portion along the perimeter forms part of upturned lip 160. The thickness of the central portion of insulating body 144 preferably ranges between 0.75 inch and 2.5 inches. For a given type of insulating foam, greater thicknesses provide a larger barrier to loss of heat from bottom end 122 of water heater 124. Using a thickness of approximately two inches provides a reasonable “R” value against thermal losses, and also serves to elevate bottom end 122 of water heater 124 by two inches or more above the supporting surface. The increased elevation of the bottom end 122 of water heater 124 assists when draining sediment through drain valve 126 by elevating bottom end 122 of water heater 124. In addition, elevating bottom end 122 of water heater 124, together with upturned lip 160, helps to keep bottom end 122 of water heater 124 from being damaged by minor floods of collected water on the underlying foundation or other supporting surface.

Insulating pad 120 may be circular in shape, and have a lateral size, i.e., diameter, commensurate with the bottom diameter of water heater 124. However, insulating pad 120 need not be circular; for example, insulating pad 120 could be more square in shape, if desired, and in that case, its lateral dimensions, i.e., its length and width, would preferably each be slightly larger than the diameter of bottom end 122 of water heater 124.

Still referring to FIG. 4, insulating body 144 is encased within a molded plastic cover 146 that generally surrounds insulating body 144. Molded plastic cover 146 is preferably made from a roto-molded plastic resin, including either polyethylene or polypropylene. Plastic cover 146 serves to protect insulating body 144 from exposure to water, hydrocarbon solvents, ultraviolet rays, and physical impact by tools, children, and/or rodents. Preferably, upturned lip 160 extends approximately two inches above upper surface 140 of the central portion of insulating pad 120. As shown in FIG. 4, drain hole 180 is provided in upturned lip 160, approximately one inch above upper surface 140. Drain hole 180 selectively drains water that may have collected upon upper surface 140, once the level of such collected water reaches the height of drain hole 180.

The insulating pad 120 shown in FIG. 4 may be formed by at least the two methods described above in regard to insulating pad 20. Preferred materials for constructing insulating pad 120 are the same materials described above in reference to insulating pad 20.

FIG. 5 illustrates an alternate configuration for forming an upturned lip for the insulating pad. In FIG. 5, insulating pad 220 includes an upper surface 240 for receiving the bottom end 122 of water heater 124, and an opposing lower surface 242 for resting upon a supporting surface. Insulating pad 220 includes an inner insulating body 244 made of an insulating foam, preferably of polyurethane, polyethylene, or polystyrene. In the embodiment illustrated in FIG. 5, insulating body 244 has a substantially uniform height, or thickness, preferably ranging between 0.75 inch and 2.5 inches. Molded plastic cover 260 is formed, encasing and surrounding insulating body 244, and also providing upturned lip 260. The methods and materials for forming insulating body 244 and molded plastic cover 260 are preferably the same as those methods and materials already described above in forming insulating pads 20 and 120. Drain hole 280, shown in FIG. 5, serves the same purpose as drain hole 180 in FIG. 4.

Those skilled in the art will now appreciate that an insulating pad has been disclosed herein for insulating the bottom of a hot water heater tank against thermal losses, while resisting damage due to hydrocarbon solvents, ultraviolet rays, and/or physical impact. The described insulating pad also helps to isolate the base of the associated hot water heater from minor flooding upon the supporting surface. When provided with an upturned lip, the insulating pad also serves to collect small amounts of runoff and/or leaking water originating with the hot water heater itself, thereby helping to prevent water damage to surrounding structures. In addition, the described insulating pad can be manufactured relatively easily and inexpensively.

While the present invention has been described with respect to preferred embodiments thereof, such description is for illustrative purposes only, and is not to be construed as limiting the scope of the invention. Various modifications and changes may be made to the described embodiments by those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims. 

I claim:
 1. An insulated base for a water heater, the water heater including a generally circular bottom end having a bottom diameter, and the insulated base being adapted for placement below the bottom end of the water heater, the insulated base comprising in combination: an insulating body made of insulating foam, the insulating body having a thickness ranging between 0.75 inch and 2.5 inches, and having a lateral size commensurate with the bottom diameter of the water heater; and a molded plastic cover generally surrounding the insulating body.
 2. The insulated base for a water heater recited in claim 1 wherein the insulating body is made from polyurethane.
 3. The insulated base for a water heater recited in claim 2 wherein the insulating body is made from closed-cell, high-density polyurethane foam.
 4. The insulated base for a water heater recited in claim 1 wherein the insulating body is made from polyethylene.
 5. The insulated base for a water heater recited in claim 4 wherein the insulating body is made from closed-cell, high-density polyethylene foam.
 6. The insulated base for a water heater recited in claim 1 wherein the insulating body is made from polystyrene.
 7. The insulated base for a water heater recited in claim 1 wherein the insulating body is made of sprayable insulating foam injected into the molded plastic cover.
 8. The insulated base for a water heater recited in claim 7 wherein the sprayable insulating foam is open-cell spray polyurethane foam.
 9. The insulated base for a water heater recited in claim 7 wherein the sprayable insulating foam is closed-cell spray polyurethane foam.
 10. The insulated base for a water heater recited in claim 1 wherein the molded plastic cover is made from roto-molded plastic resin.
 11. The insulated base for a water heater recited in claim 10 wherein the roto-molded plastic resin is polyethylene.
 12. The insulated base for a water heater recited in claim 10 wherein the roto-molded plastic resin is polypropylene.
 13. The insulated base for a water heater recited in claim 1 wherein the molded plastic cover includes a lower surface for resting upon a supporting surface, and the molded plastic cover also including an opposing upper surface for receiving the bottom end of the water heater.
 14. The insulated base for a water heater recited in claim 13 wherein the upper surface of the molded plastic cover includes an outer perimeter, the outer perimeter having an upturned lip extending around the upper surface of the molded plastic cover.
 15. The insulated base for a water heater recited in claim 14 wherein the upturned lip includes a drain hole for selectively draining water collected upon the upper surface. 